First cycle
Selected problem
What are photons and phonons?
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Then try to understand what does it say about the problem.
Figure1: Normal modes of vibration progression through a crystal. The amplitude of the motion has been exaggerated for ease of viewing; in an actual crystal, it is typically much smaller than the lattice spacing.
In the similar way that photons are particles of light, phonons are particles of sound or heat. Basically, they are quantized energy, which shows wave-like and particle-like properties simultaneously.
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2. Photons (particles that carry light and electromagnetic) do not interact with each other if they have different wavelength. However, phonons at different frequencies can mix together and generate superimposed wavelength.
Second cycle
Selected problem
We already know the application of photons, what is the application of phonons?
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